# Callback functions

The module has several colback functions that are called as they are initialized:

* `def on_init` - Called after Stage2, due to the peculiarities of asynchronous programming the availability of the database is not guaranteed
* `async def on_db_ready` - Called immediately after full database initialization, useful to use if you need to work with the database immediately after startup

Example usage:

```
async def on_db_ready(self):
    async with self.db.session_maker() as session:
        # load chat states from database
```


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